This invention relates to Giardia lamblia, in general, and in particular to a method for treating giardiasis, caused by Giardia lamblia.
Giardia lamblia is the most frequently identified enteric parasite in the United States. Pediatr. Clin. North AM, Jun. 1988, 35(3), 565-77. It is purportedly the most common pathogenic enteric protozoan and is an important cause of gastro-intestinal disease throughout the world. It is an especially critical problem in third-world countries and presents a particularly difficult problem when it infects children.
In one study of infections in malnourished Jamaican children, in those instances of infection where an aetiological agent was identified, Giardia lamblia was the most common enteric pathogen. J. Trop. Med. Hyg., 91(4), 173-80, Aug. 1988. In another study of households located in the Nile Delta region of Egypt, involving 724 children, only one child remained Giardia-negative during the study. Am. J. Epidemiol., 127(6), 1272-81, Jun. 1988.
Unfortunately, although Giardia lamblia is such a ubiquitous pathogenic protozoan, inhabiting the upper portion of the small intestines, causing both acute and chronic diarrhea and malabsorption, the presently used therapeutic agents are less than satisfactory. In fact, the therapeutic agents currently of choice were developed principally for treatment of other infections and later found to be efficacious against Giardia lamblia. Typically, giardiasis is treated with metronidazole, tinidazole, quinacrine, or furazolidone, but such treatment is typically associated with undesirable side effects and is not always successful.
Pentamidine has been known for decades and was originally shown to be useful for the treatment of trypanosomiasis. Of more recent time, pentamidine has been found to be extremely useful in the treatment of pneumocystis carinii pneumonia, especially in immunocompromised patients suffering from the acquired immunodeficiency syndrome (AIDS). However, pentamidine has not heretofore been known to have utility in the treatment of giardiasis.
It goes without saying that in view of the magnitude of Giardia lamblia infection throughout the world, and the lack of a satisfactory agent for the treatment thereof, an urgent need exists for a moreeffective anti-Giardia agent having good therapeutic properties.